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The Basics of Nonferrous Metallurgy

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High Strength Copper-Titanium Alloys: Part Two

Copper-titanium alloys consist mainly of copper and contain 2 to 6% by weight of titanium, the preferable content of titanium being 3 to 5% by weight. If they contain less than 2% by weight of titanium, no appreciable effect of age-hardening can be expected, and the addition of more than 6% by weight of titanium does not provide a correspondingly improved effect of age-hardening as the excess over 6% is increased.

Historical Development of Aluminum Production and Application

The historian who would trace the story of aluminum has a comparatively easy task. It is not referred to in the writings of the "ancients", nor in classical records; aluminum is a product of the present age. In 1886, in a woodshed at Oberlin, Ohio, and in a tannery at Gentilly, France, two young men almost simultaneously unlocked the door to low-cost production of aluminum from its oxide. Charles Martin Hall, in February 1886, and Paul Louis Toussaint Heroult, in April 1886, determined that molten cryolite was an effective solvent for the electrolysis of alumina. The age of light metals was born.

Hot Forming of Al-Mg Alloy Sheet

Highly ductile pure aluminum is not suitable for the mass-produced car because of its low strength and proneness to handling damage. Some years ago the stronger, aluminum-magnesium alloys were used for the press forming of panels at ambient temperature, but these alloys were less formable than extra deep-drawing quality steel due to their low r-values and reduced ductility.

Hot tearing Susceptibility in Aluminum Alloys

Solidification cracks are a serious threat for all types of metallic materials and can appear in several forms, stress/cold cracks or hot cracks or tears.
The main difference between these two main groups of defect is that the cold cracks appear below the non-equilibrium solidus temperature and hot tears above it.

How Deformation Affects the Mechanical Properties of Aluminum Forgings

Distortion of heat-treated aluminum forgings during machining has always been a problem. The obvious economic and engineering advantages of large aluminum forgings resulted in the US Air Force heavy press program at the end of World War II. Though they proved cost competitive, these larger forgings introduced increasingly severe machining problems due to distortion. Acceptable finished parts could be produced by competent machine shops, but often only with elaborate machining sequences and slow removal of metal.

INVAR Alloys

INVAR alloys, primarily composed of iron and nickel, are renowned for their exceptionally low thermal expansion coefficient near room temperature. Named "invariable" due to their dimensional stability at specific temperatures, these alloys exhibit unique magnetic anomalies including deviation from the Slater-Pauling curve and temperature-dependent Curie points.